feat: send conversation history to agent

cmd/sidekick-tui/main.go

@@ -153,13 +153,18 @@ func (m model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
         return m, nil
       }
       
+      m.history = append(m.history, sidekick.Message{
+        Role:    sidekick.MessageRoleUser,
+        Content: v,
+      })
+
       wrappedUser := lipgloss.NewStyle().Width(m.viewport.Width).Render(userStyle.Render("You") + "\n" + v)
       m.messages = append(m.messages, wrappedUser)
       m.textarea.Reset()
       m.viewport.SetContent(strings.Join(m.messages, "\n\n"))
       m.viewport.GotoBottom()
       m.isThinking = true
-      return m, m.runAgent(v)
+      return m, m.runAgent()
     }
 
   case agentResponseMsg:
@@ -182,9 +187,9 @@ func (m model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
   return m, tea.Batch(tiCmd, vpCmd)
 }
 
-func (m model) runAgent(prompt string) tea.Cmd {
+func (m model) runAgent() tea.Cmd {
   return func() tea.Msg {
-    res, err := m.agent.Run(context.Background(), []sidekick.Message{{Role: sidekick.MessageRoleUser, Content: prompt}}, m.pool)
+    res, err := m.agent.Run(context.Background(), m.history, m.pool)
     return agentResponseMsg{response: res, err: err}
   }
 }